ERCoCr-B Filler Wire
COREWELD ST12 ERCoCr-B Filler Wire is a cobalt-based hardfacing filler material for components that need wear resistance and performance at elevated temperatures. Welders apply it on surfaces subject to abrasion, friction and demanding operating conditions, such as cutting edges, valve seats, and sliding faces. Material selection depends on the component, its service conditions and the applicable welding procedure, so match the alloy to the job before you place an order. Review the classification, dimensions and composition limits in the datasheet before you plan a deposit.
AWS A5.21 ERCoCr-B places this alloy in the cobalt base hardfacing group, a cobalt, chromium, tungsten and carbon system that targets surfaces under wear. Hard carbides lie inside a cobalt matrix, and that structure gives the family its hardness and wear resistance. Published data for the alloy family also reports hardness retention at elevated temperatures, but COREWELD ST12 service limits are specified only in its datasheet.
Product form deserves attention. A bare cast rod arrives in straight lengths for manual deposition. A continuously supplied welding wire feeds from a spool or coil into mechanised equipment. Confirm which forms COREWELD ST12 offers before you set up a procedure.
ERCoCr-B Filler Wire, AWS A5.21 ERCoCr-B, COREWELD ST12 Filler Wire
Cobalt base composition sets the character of COREWELD ST12. Chromium and tungsten carbides in the deposit supply hardness and resistance to abrasion and friction, while the cobalt matrix holds those carbides in place. The same chemistry supports corrosion resistance and hardness retention at elevated temperatures, and each property holds only within the limits on the datasheet. Buyers can evaluate the product for sliding contact, cutting edges and flow control components. Component life depends on the base metal, joint design, welding procedure and operating environment, so no single figure applies to every job. Test a trial deposit on the actual component when the duty is severe.
Technical Specifications of COREWELD ST12
The table lists the core details of COREWELD ST12 ERCoCr-B. Entries marked for confirmation follow the official datasheet, so compare them with that document before you finalise a procedure or an order.
| Specification | Details |
| Brand | COREWELD ST12 |
| Product Name | ERCoCr-B Filler Wire |
| AWS Classification | ERCoCr-B |
| Applicable Standard | AWS A5.21 / ASME SFA A5.21 |
| Material Type | Cobalt Base Hardfacing Alloy (Bare Wire Cobalt) |
| Product Form | Bare Cast Rod (Referred to as “Type 12 bare rod”) |
Chemical Composition of ERCoCr-B Filler Wire
| Element | AWS Requirement (%) | Typical Deposit (%) |
| Cobalt (Co) | Remainder | Balance |
| Chromium (Cr) | 26 – 32 | 30.4 |
| Carbon (C) | 1.2 – 1.7 | 1.5 |
| Tungsten (W) | 7.0 – 9.5 | 8.5 |
| Nickel (Ni) | 3.0 max | 2.2 |
| Iron (Fe) | 3.0 max | 2.3 |
| Molybdenum (Mo) | 1.0 max | 0.1 |
| Manganese (Mn) | 1.0 max | 0.06 |
| Silicon (Si) | 2.0 max | 1.3 |
| Other | 0.50 max | Not specified |
Mechanical Properties of AWS A5.21 ERCoCr-B
| Property | Value |
| Hardness | High hardness (Specific HRC / HB value is not specified in the datasheet, but it is non-forgeable and machined with difficulty using carbide tools) |
| Wear Resistance | High abrasion resistance and good corrosion resistance (carbide-strengthened cobalt matrix) |
Equivalent Grades of ERCoCr-B
| System | Designation |
| AWS A5.21 | ERCoCr-B |
| ASME SFA 5.21 | ERCoCr-B |
| UNS | R30012 |
| AWS A5.13 (electrode form) | ECoCr-B |
| Trade name | Stellite 12 |
Applications of ERCoCr-B Filler Material
- Cutting tool edges and knives
- Saw teeth and guides
- Valve seats and trim
- Pump sleeves and wear rings
- Shear blades
- Extruder screws and flights
- Bearing and sliding surfaces
- Chemical process equipment parts
Manufacturing Process of ERCoCr-B Filler Material
- Material selection of cobalt, chromium, tungsten and carbon feedstock
- Alloying and melting to the target composition
- Forming process into the supplied rod or wire form
- Composite filler metal selection for the intended hardfacing duty
Why Choose COREWELD ST12 ERCoCr-B?
Start with the documents when you assess COREWELD ST12 for a hardfacing requirement. The product carries the AWS A5.21 ERCoCr-B classification, and the official datasheet lists the alloy details, available dimensions and packaging in one place. Compare those entries with your base material, deposition process and service conditions. Review the datasheet to confirm alloy details and application suitability before you commit to a purchase. A datasheet does not replace a procedure qualification, so validate the weld on your own component. Buyers who need dimensional or packaging confirmation can raise it at the enquiry stage, which keeps the specification aligned with the job.
Supply Options and Technical Support
Enquire about ERCoCr-B Filler Wire by stating the product form, diameter, rod length, quantity and packaging you need. Add the component material, service temperature and wear conditions, because these details shape the product recommendation. Ask the company to confirm supply terms, delivery schedules and technical support when you enquire.
Send your requirement with the component details to request a quotation.
Products
FAQ's
What is ERCoCr-B filler wire used for?
It hardfaces components that face abrasion, friction and elevated temperatures. Targets include cutting edges, saw teeth, valve seats and extruder screws, where a cobalt base deposit protects the working surface.
What is the AWS A5.21 ERCoCr-B classification?
AWS A5.21 sets requirements for bare surfacing electrodes and rods. ERCoCr-B names the cobalt, chromium and tungsten alloy within that standard, and it sits between the A and C grades.
What is COREWELD ST12?
COREWELD ST12 is the brand name for this cobalt base hardfacing product, supplied to the ERCoCr-B classification. Its datasheet carries the product details, including form, dimensions and packaging, so read it before you specify the product.
What is the difference between ERCoCr-B and other cobalt base hardfacing alloys?
ERCoCr-B holds a higher carbide fraction than the A grade, which raises abrasion resistance at some cost to toughness. The C grade carries more carbon again, so ERCoCr-B occupies the middle ground.
Which industries use ERCoCr-B filler material?
Valve manufacturing, cutting tool production, plastics extrusion, power generation and chemical processing apply it to wear surfaces. Check suitability for your own duty against the datasheet before you select it for a new component.
What product forms and sizes are available for COREWELD ST12?
The datasheet lists the confirmed forms, diameters, rod lengths and packaging for COREWELD ST12. Send your preferred form and dimensions with an enquiry to confirm current availability and packaging for your order.